Apparatus for collecting precious metals.



613.6111111. APPARATUS FOR COLLECTING PRECIOUS METALS.

APPLICATION FILED AUG. 29, 1910.

Patented Mar. 1s, 1913.

LAWRENCE 1B. GRY, OF BOSTON,

MASSACHUSETTS, ASSIGNOR VACUUM JDREDGING COMPANY, OF WILMINGTON,DELAWARE, OF DELW.

TO HYDRAULIC A CORPORATION Specification of Letters Patent.

Patented raar. le, rara.

Application filed August 29, N10. Serial N o. 579,409.

To all 'whom t may concern:

-Be it known that ll, LAWRENCE' B.. GRAY, ot Boston,.inthe county otSudolk and State of Massachusetts, have invented certain new and usefulimprovements in Apparatus for Collecting Precious Metals, of which thefollowing is a specification.

lThis invention relates to an apparatus adapted to be used in placermining tor collecting the precious metals when the same are separated bywashing from the deposits of sediment in which they are contained.

The particular object of the present invention is to collect thoseparticles of the metals which are too line to sink into the' watercarrying them, and which are known as Heat may be. Y Accordingly theapparatus consists ot a sluicel or flume through which a stream ot watercarrying the deposit-s with which the particles of precious metals aremingled, is led, with a device of such charactei` as to be able toretain the located in such a position as to intercept those particleswhich oat upon the surface oit the stream. Also, the apparatus includes,in combination with said device,y a set ot movable battles operated bythe stream toy bank up the water adjacent to t-he device, whilepermitting solid matter carried by the stream to pass, which is also amotor for so moving` the device as to` present di'erent parts ot its surtace to the doa'ting metal, and to carry such surface pactand in-contact with a scraper which removes the material adhering to suchsurface.

lin the accompanying `drawings l have illustrated an apparatus'embodying the principles ot my invention, and being one ci many forms inwhich these principles may be embodied. Figure l represents' theapparatus in side elevation., Fig. 2 representsa longitudinal section otthe same. lig. 3 is a plan view, and Fig. d is a cross section. rlhesame referenceA characters indicate the same parte in all the ltigures.

Att the outset ll'desire to state that this apparatus is adaptedfto beused for collecting thehne particles ot any-ot the precious gold, Heatsilver, etc.,"as the case.

particles of metal, andacted upon as gold, for the purpose merely ofconvenience of description, and to avoid theuse of too many words,without, howlever, intending to limit myself in any manner to the kindof metals which l propose to save by the use of the apparatus. l

Referring to the drawings, a represents a flume or sluice through whichthe water charged with the gravel and dirt containing gold is caused toflow. At a suitable point in the sluice is located 4a drum b which iscarried by trunnions c having bearings in boxes d in thesides of thesluice. The drum is so mounted that its lower part dips into t-he waterin She sluice, and is preferably adjustable/ so that it maybe thuspartly submerged when the water is at any height, and may also besubmerged to a greater or less extent as desired. yFor this purpose theboxes al are adjustably contained in vertical guides e, and are providedwith adjusting yscrews f passing through yokes g and carrying nuts k.The yokes cross' the guideways and the nuts bear on the yokes, therebyenabling the boxes and with them the drum .to be adjusted up or down.vln the bottom olf' the sluice, directly below the drum b `is a shallow'pocket z' containing a quantity of mercury. 'lFhe drum is preferablymade ot copper, with its outer surface silver plated, and covered withmercury. The mercury is necessary to form an amalgam with and piclr upthe gold Heating on the stream, and the plating ot' silver on thedrum'is necessary to malte the mercury stick and spread over itssurface, while copper is used as the material for making the drum,because it is best adapted to retain a plating of silver.

Above thedrum'li's a trough or tank y' containing mercury,and'liavingioutlets 7" in its bottom 'through which `.small quantitiesot the mercury are-l continually ted upon the drum. At the rear side ofthe drum is a scraper k which bears against the surface of the drum, andwhen the latter is rotated, scrapes olf the amalgam upon its `surface.The scraper also is above the mercury in the pocket z' and the amalgamwhich falls from it drps into the mercury and is kept by the latter frombeing carried on with the water and gravel. This descending current ofamalgam falls through the stream of pulp passing betweenthe drum andpocket and catches any particles of metal which may escape the drum. Thescraper may be a brush or brushes, and is conveniently a strip of wood,leather or the like, held at one edge in and projecting edgewise from abar Z, the latter being pressed yieldingly toward the drum by springs Zand supported by studs Z2 passing through a stationary bar m spanningthe. flume. In the embodiment of the invention here shown, the bar m isfastened to plates n. and n which are slotted so as t-o slip over theboxes d, and are contained between t-he sides of the flume and the endsof the drum. The mercury supply trough y' is also secured at its ends tothese plates. The plates are further, connected together by a cross-baro, which also provides a guard for the drum, protecting the same frominjury. These, details of construction, however, are merely optional andmay be varied and modified without departing from the spirit of theinvention. On the pins Z2 previously referred to are threaded adjustingnuts y) which secure the scraper.

Secured'to the boxes Z in which the drum trunnions are held are platesshown in section in Fig. 4, and designated by the letter n2, which coverthe openings in the walls of the sluice wherein are/the vertical guidese for 4the boxes. vThe plates n2' are arranged both on the inside andoutside of each wall of the sluice and cover the spaces between theguides so that water will not. leak out even when the'boxes are raisedabove the bottoms of such spaces as shown in Fig. 4. The plates n-n/above described have slots which enable them to fit over the inner coverplates n2.

A convenient motive mechanism for rotating the drum is found in thewater wheels g and g, the shafts 1' and r of which are supported inbearings on the opposite walls of the flume. These water wheels arecaused to rotate in unison by means of gears 8 and son their shaftsrespectively meshing with an intermediate idler wheel s2. On the shaftof one of the wheels is a sprocket t which drives, by means of a chaint', a sprocketl t2 on the shaft of the drum. Any suitable form of waterwheel may be used differing if need be from that here shown, whichconsists merely of vanes secured to armed s iders on th shafts r and 7*.By reason o the water wheels the drum is kept in rotation in such adirection that the portion which dips into the water travels in the samedirection as the stream. Preferably the wheels are so arranged that oneof the blades of one dips squarely into the stream while the blades ofthe other are inclined to the flow of the stream. In other words,whenever a blade of one of the wheels projects vertically downward fromits axis the two low'ermost blades of the other wheel are inclined andmake equal angles with a vertical line passing through the axis of thatwheel. There is a coaction between the paddle wheels and the amalgamatindrum in the recovery of precious metal an irrespective of the functionwhich said paddle wheels have of rotating the drum. This is that theblades of the paddle wheels act as revolving and movable battles or damswhich obstruct the ow of water through the sluice, causing the water toback up around the drum to a height greater than that due to the depthat which the drum is set in the sluice, and periodically withdraw toallow the gravel and stones carried in the stream, to pass on down thesluice. To explain further, it is to be understood thatthe stream whichpasses through theV sluice carries gravel and stones, some of the latterof considerable size. It is objectionable to set the drum so near thebottom of the sluice that there will be any danger of its being struckby these stones, as the stones would dent the drum, preventing an evencoating of the quicksilver and removal from the drum of amalgam. Neitheris it feasible in many instances to direct alarge volume of waterthrough the sluice in proportion to the amount of gravel and stones soas to submerge the latter to any great depth, because in many miningregions the supply of water is limited and must not be wasted. Hence itis usually impossible to set the drum so that it dips much below thesurface of the freely fiowing stream without liability of the drum beingstruck by stones. On the other hand the etiiciency of the apparatus incollecting float metals is greatly increased by having as great anextent as possible of the surface of the drum in contact with the water.Hence the value of the revolving baies or paddles q, q. When any one ofthese paddles extends downwardly intothe stream, it largely impedes theHow thereof, causing the level to rise locally in the vicinity of thedrum, increasing the extent of the submerged surface of the drum,without any increase in the actual quantity of water flowing, andwithout incurring danger of stones striking the drum. It is furthernecessary that the blades should be spaced angularly wide apart, inorder to avoid danger of the stones wedging between the blades, hencethey are set at an obtuse angle with each other as shown. Finally it isnecessary that the backed up condition of the water should bepractically continuous,

ipagees while at the same time provision be made to prevent theaccumulationv of vstone and gravel, hence the provision'of the twowheels or sets' of balles, so arranged that when the baes of one set areso lacedI as not to obstruct the stream, a ba e of the other ,set

does obstruct the stream. The two sets oli balles in combinationconstitute a sort of.

lock which permits the solid matter to pass nishes an amalgamatingsurface directly in the path ofthe float same, and causes a fressurfaceto be'constantly presented to the advancing gold, so that it willbe in condition to pick up the goldas fast as4 it is carried down bytheflowing stream.' This edect is Vproduced by vvirtue of the rotarymovement of the drum inthe manner above described, The apparatus listhus very simple and as it is driven by the power of the streamitse1f,it is economical as well. Such ofthe .precious metal as sinksduring the pro ress of the stream through the'sluioe and alls into thepocket z' is retained by the quick'silver therein, and any of themetalwhich escapes contact with old to pick up the the mercury on thedrum land that in the pocket, is caught by the amalgam 'passing throughthe stream from the drum to the pocket and saved. Thus a-descending cur-Atain of ments the action oft e mereuryon the drum and the mercury oramalgam in the pocket in retaining the preciousmetals.v

ll claim:

l. itn'amalgamating apparatus comprising an open sluice or flume, a drumhaving a smoothl amalgamating surface supported between .the walls ofthe sluiceabove thev bottom of the sluice, so as tocollect the finefloat metal and permit the gravel to pass' freely, beneath it, a mercurypocket below and spaced' from the drum, means for rotatin lengt of thedrum and bearing on its'surface at a point over said pocket, and adaptedto dischar e the amalgam directly into the ocket an thi-ou hA the streamof pulp passing between the um and pocket.

2. An amalgamatingapparatus comprising an open sluice or Hume, a drumhaving' a smooth amalgamating surface supported between thewalls of thesluice at a height above the bottom of the sluice whereby to the top of.entire length, for

lticles l of metal i caught.

vwhereby to allow drum set into said sluice,

ing

amalgam is provided which supple'v 'combination with -gamating surface,

the drum, a scraper extending the voir secured at its opposite I collectline floating particles of'metal borne by the stream passing through'the sluicev means for continuously feeding mercury to the drum along itsentire length, and a scraper bearing on the drum along its continuouslyremoving amalgaml therefrom and producing a descending current .ofamalgam, through which the stream flows and by which parescaping thedrum are .3. In an amalgamating apparatus the4 combination with a sluiceof an amalgamating-drum set'therein and means for maiutaining arelatively high level of .water at the locality of said drum whilepermitting y .the drum to remain sufficiently high above ythe bottom ofthe sluice topermit stones to pass without striking it, said meanscomprising a pair of baihes located at the downstream side of the drumwhereby to obstruct the How of water, said bafi'ies being operated bythe crrent so'as alternately to be withdrawn from and projected into'lthe drum, 'solid substances -to pass them.A

y4f. In an amalgamatingapparatus the combination'with a sluice, anamalgamating a plurality of sets of revolving bames Vlocated atz'thedownstream side `of the drum, each of said sets of baiies comprising ashaft and blades 'seand making obcured radially to said shaft tu'seangles with one another, said shafts begeared together yto rotate inunison, and

being driven by impingement of the' stream against the blades, theblades on thev shafts A being sofarranged that when afblad'e of eitherdips into the stream,the blades of' 4 the othervare withdrawn therefrom.

-5. 'In an amalgamating apparatus the drum havin `journals rotatablyheld in the side walls o the sluice, and having an amala vmercuryreservoir, and means for removably supporting said reser-v voir in closeproximity to the upper side of vthe drum,

,and being secured at its ends thereto.

6. I [n an amalgamating apparatus, the combinatipn with an open sluicetrume, a drumrhaving walls of the sluice,-plates contained between theends of the brace the boxes, wherebyt e plates-are sup-4 portedv andheld in place,

a mercury reserends to the plates an'd extending from one to the otherover thel top of the drum,. arranged to feed meran open sluice or flume,a\

drum and the side'wallsjofy the sluice, having slots to ass over andemjournals, boxes in ywhich said yournals are contained mounted in theside cury upon the drum, a bar at one side of l such relation to oneanother when so rethe drum secured at its ends to the plates, a moved asto permit ready replacement. l0 scraper supported by said bar andmovable In testimony whereof I have aflxed my toward and from the drum,and springs signature, in presence of two witnesses.

1 acting between the bar and scraper to press LAWRENCE B. GRAY.

the latter against the drum; the plates, res- Witnesses: ervoir andscraper being removable to- A. H. BROWN,

`gather from the drum, and being held in P. W. PEzzETTI.

